Hospital bed



Jan. 14, 1958 E. D. OLSEN ,8

HOSPITAL BED Filed June 15, 1955 2 Sheets-Sheet 1 INVENTOR Fi .2. fA/ERY 0455 ATTORNEYS E. D. OLSEN HOSPITAL BED Jan. 14, 1958 2 Sheets-Sheet 2 Filed June 15, 1953 INVENTOR. 545W 0 OLSEN BY ATTORNEYS United States PatentOfiFice HOSPITAL BED Emery D. Olsen, Oakland, Calif.

Application June 15, 1953, Serial No. 361,745

4 Claims. (Cl. -68) The present invention relates to an improved adjustable bed of the general type commonly employed in hosp tals and more particularly to an improved powered ad ustment means for such a bed. Hospital beds, for example, are conventionally provided with certain adjustable means whereby the head and foot portions of the bed may be raised or lowered either for added comfort of the occupant or for particular medlcal treatments. Normally these beds are provided with manually operable cranks disposed at the end of the bed and connected to screws that upon rotation urge the bed springs into some adjusted position. This central adjustable bed portion, aside from the bed ends, is not eas1ly or rapidly movable by the nurse or other attendant when the bed contains any great weight and it is normally not possible for the bed occupant to accomplish the adjustment.

The presentinvention provides a power driven adjustment means which may be readily operated either by the beds occupant or an attendant and which rapidly adjusts the bed to any desired position with a minimum of elfort. Fingertip control of all desired bed adjustments is provided with a minimum of power equipment and connecting linkages so that a bed equipped with the improved means of the invention may be more rapidly adjusted with less effort and without requiring an attendant to operate the adjusting mechanism.

It is an object of the present invention to improved adjustable hospital bed.

It is another object of the present invention to provide an adjustable hospital bed having manually controllable power driven adjusting means.

It is a further object of the present invention to provide an improved hospital bed having electrically operated head, foot and knee adjustments.

A still further object of the present invention is to pro vide an improved adjustable bed having motor driven adjusting means controllable by the occupant.

It is another object of the present invention to provide an improved adjustment means having a motor engageable to adjust the head portion and to raise, lower, and bend the foot portion.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawings accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawings and description may be adopted within the scope of the invention as set forth in the claims.

A preferred embodiment of the invention is illustrated in the accompanying drawings wherein:

Figure 1 is a plan view of a hospital bed incorporating the present invention;

Figure 2 is an elevational view of the hospital bedof Figure 1;

provide an Figure 3 is a sectional view taken at 3--3 of Figure 2;

aster/4 Patented Jan. 14, 1958 Figure 4 is a sectional view taken at 44 of Figure 3;

Figure 5 is an enlarged sectional view taken at 5-5 of Figure l and showing the foot of the bed bent for knee lift and showing in phantom the foot of the bed raised.

Figure 6 is an enlarged sectional view taken at 6-6 of Figure 1 and showing the head of the bed raised.

Considering now the structural details of the illustrated embodiment of the invention and referring to the drawings, there is provided a hospital bed having a head member 11, including spaced vertical posts joined together and a foot member 12 likewise constituted, bothbeing preferably provided with wheels at the bottom ends thereof for facile bed movement. Mounted between the head and foot members is a central portion 13 which includes a rigid rectangular frame including side rails 14 and head and foot rails 16 and 17 respectively, with the frame being removably mounted between the head and foot members 11 and 12 as by co-operating projections thereon in any suitable manner. Mounted atop the rigid frame and substantially co-extensive therewith is an adjustable frame which may be joined to the rigid frame by plates 18 at the center of each of side rails 14 and rigidly joined both to side rails 14 and like stationary members 19 on the adjustable frame. The adjustable frame includes a three sided planar head portion 21 formed of angle iron or the like and pivotally joined at the free ends thereof to the central stationary portion 19. Also included in the adjustable frame is a three sided foot portion 22 like the head portion 21 but pivotally linked at its free ends to a pair of short extensions 25 upon a pair of link rails 23 that are in turn pivotally joined to the central stationary rail members 19.

The above described bed frame is so constituted as to be positionable in a variety of different positions by varying the relative disposition of the parts of the adjustable frame and flexible bed springs (not shown) are mounted upon the adjustable frame so that one using the bed by lying upon the springs, or upon bedding disposed on the springs, may be positioned as desired. In order to facilitate adjustment of the bed contour there is provided power driven adjusting means 24 co-operating with the adjustable frame and operating to vary the relative disposition of the parts thereof. This adjusting means in cludes a housing 26 which may be substantially enclosed or may include only side and bottom members, as shown, and which is mounted beneath the rigid bed frame adjacent one side thereof and preferably near the head of the bed; additional cross members may be attached to the rigid bed frame for mounting housing 26 and the adjusting means 24. Housing 26 includes a pair of vertically displaced horizontal plates 27 and 28 rigidly positioned to carry portions of the adjusting means 24 and on the upper plate 27 there is mounted two sets of drive gears with the forward set including two parallel displaced fiber discs 31 and 32 mounted for rotation and each having bevel gears formed on mutually presented faces thereof. A bevel gear 33 on the end of a shaft 34 mounted for rotation in the front wall of housing 26 is disposed intermediate fiber discs 31 and 32 in engagement with the bevel gears thereon so that rotation of either disc drives the shaft 34. Similarly the rear drive gears include a second pair of parallel displaced fiber discs 36 and 37 mounted for rotation on upper housing plate 27 with bevel gears formed on the mutually presented disc faces and a bevel gear 38 disposed intermediate discs 36 and 37 in engagement with the disc gear surfaces and secured to a shaft 39 mounted for rotation on the rear. wall of housing 26. The front and rear drive gears are selectively rotated by a pair of drive wheels 41 and 42 made of iron or the like and rigidly mounted upon a drive shaft 43 for rotation therewith and being slidable longitudinally of said shaft of which thecentral portion thereof has a square cross section. Drive wheels 41 and 42 are separated on shaft 43 slightly less than the separation of the discs in each of the drive gear trains and the drive wheels are aligned parallel to the drive gear discs intermediate the front and rear drive gears and slightly displaced from each. Driving engagement of the drive wheels and selected fiber discs is facilitated by forming the peripheral surface of the discs convexly and the cooperating surface of the drive wheels concavely.

Selective actuation of the drive gears is accomplished by the provision of means to move the drive wheels 41 and 42 into peripheral engagement with individual fiber discs and to this end drive wheel shaft 43 is rotatably mounted near its ends in a pair ofvertically disposed bars 4 and. 46 that extend downward from upper housing plate 27 and are locked upon a Cradle shaft 47 mounted for rotation upon lower housing plate 28. This arrangement comprises a cradle with the drive wheels 41 and 42 and drive shaft 43 carrying same being mounted by bars 44 and 46 to rock back and forth upon cradle shaft 47 between the front and rear drive gear trains. The aforementioned square section of drive shaft 43 extends between Cradle bars 44 and 46 and drive wheels 41 and 42 which are mounted thereon for slidable longitudinal movement arerigidly joined together so that they remain a fixed distance apart which is less than the separation of the pairs of fiber discs in each drive gear train at least by the width of a fiber disc drive surface as best shown in Figure 3. There is provided by the cradle mounting of the drive wheels 41 and 42 means for adjusting the position thereof so that any single one of the fiber discs may be engaged and driven by sliding the drive wheels longitudinally of the drive shaft 43 to align one of; the drive wheels with one of the discs of each drive train and rocking the drive shaft and carried drive "wheels to produce peripheral engagement ofone drive wheel with one disc, as for example wheel 42 and disc 32 in the position of Figures 3 and 4. These movements of the drive wheels may be readily accomplished by a handle 48 which extends vertically upward beside the bed frame and which is joined to drive wheels 41 and 42 as at the connection thereof by suitable linkage, as shown, including means accommodating the rotational motion of the drive wheels while maintaining same in the desired position.

Propulsion of the above described drive means is provided by an electric motor 49 which may be mounted on the lower level of housing 26 and which has a pulley 51 secured to the. motor shaft for engagement with a belt- 52 looped about a second pulley 53 rigidly secured to the drive shaft 43. Control of the motor 49 is provided by a pair of pushbutton switches 54 which are electrically connected between the motor 49 and a source of electrical current (not shown) and which are physically positioned one on either side of one end of the drive shaft 43 so that rocking of the drive shaft to engage a drive wheel with a disc in the drive gear train causes the drive shaft or an extension thereon to actuate the pushbutton and to energize the drive motor 49. In order to stabilize the cradle in center or neutral position the lower ends of the cradle bars 44 and 46 may extend into sliding contact with the upper surface of housing mounting plate 28 whereby the cradle is normally held upright and a slight force is necessary to rock same otf center, as will be seen from Figure 4. Suitable bearings and mounting means may be provided to adequately mount the various elements of the invention as shown in the drawings.

The above described drive means will be seen to include shifting means whereby any single disc in the drive gear train may be driven by sliding the drive wheels on the drive shaft andby rocking the cradle mounted drive shaft to engage a drive wheel with the desired disc.

Considering now the displacement mechanism operated" by the'drivemeans to vary the relative position of the portions of the adjustable'bed frame it is noted that thecombination of the two fiber discs and engaging bevel gear in each drive gear train causes the gear shafts 34 and 39 to be rotatable in either direction. Thus for example considering the forward drive gear train, engagement of drive wheel 42 with disc 32 rotates bevel gear 33 and shaft 34 in one direction while engagement of drive wheel 41 with fiber disc 31 rotates bevel gear 33 and shaft 34 in the other direction. The head displacement mechanism includes a pinion gear 56 secured to one end of a shaft horizontally mounted for rotation and in turn driven through bevel gears and appropriate shafting from a bevel gear 57 mounted on the end of shaft 34. Pinion gear 56 is preferably disposed centrally of the sides of the bed near the head thereof and suitable drive mechanism is provided to transfer the rotation of the driven bevel gear 57 thereto. There is provided in engagement with pinion gear 56 a sector gear 58 that is rigidly secured to a shaft 59 extending transversely of the bed at the head thereof and mounted for rotation beneath the rigid frame thereof as by means attached to frame member 16. There is rigidly attached to each end of sector gear shaft 59 a crank arm 61 which normally extends downwardly therefrom away from the head of the bed and which is in turn connected to head portion 21 of the adjustable frame by a link 62 pivotally joined to the crank arm 61 and to the head portion 21.

With, the above described head displacement mechanism engagement of one of the drive wheels with either of the fiber discs in the forward drive gear train rotates bevel gear 33 and shaft 34 and this motion is transferred to the piniongear 56 which thereby drives sector gear 58 in engagement therewith to rotate attached shaft 59. Rotation of shaft 59 also rotates crank arms 61 rigidly attached thereto and the translation of the ends of the crank arms, is transmitted through links 62' to the head portion 21' of the adjustable frame thereby pivoting this head portion to. raiseor lower same depending upon the direction of rotation of, the drive gear train as selected by positioning handle 48. The head portion 21 of the adjustable frame is thus readily movable into and out of raised position such as illustrated in Figure 6.

The foot displacement mechanism is operated by a bevel gear 66 mounted upon the end of rear drive gear shaft 39 and transmitting rotational motion through a suitable gear and, shafting, to a horizontally disposed axle or shaft 67 extending longitudinally of the bed toward the foot thereof and mounted for rotation beneath the rigid bed frame. Shaft 67 does, not extend to the foot of the bed but instead is attached to an elongated screw 68 by a universal joint69, screw 68 extending substantially to the foot 12 of the bed. A screw follower 71 consisting of an internally threaded cylinder threadably engages screw 68 and a pair of like links 72 and 73 are pivotally mounted near the center of screw follower 71 at the top:

and bottom thereof respectively. The lower link 73 is connected at its lower end to a pin 74 that rides in horizontal slots 76 in the upright flanges of a horizontally disposed channel 77 rigidly mounted below the level of shaft 67 adjacent the foot ofthe bed as by a hanger joined to end piece 17 of the rigid bed frame and depending therefrom. The upper link 72 on screw follower 71 is pivotally connected at its outer end to the end of foot portion 22 of the adjustable bed frame.

Considering the operation of the foot displacement mechanism it will be seen that rocking of the cradle mounted drive shaft 43 toward the foot of the bed engages one -of the drive wheels ,41 or 42 with one of the gear surfaces on the fiber disc-s to rotate in the desired direction.

thus attached screw 68 rotates. As screw 68 is not longitudinally displaceable; rotation of'same causes screw Shaft 67 is thus rotated from bevel gear 66' upon shaft 39 through appropriate drive connections andv follower 71 to travel along the screw in one or the other direction depending upon the direction of rotation of the screw and the direction of the threads thereon. With follower 71 driven toward the foot of the bed from the position shown in Figure 2 lower link 73 cannot move toward the foot of the bed as the pin 74 at the end thereof is at the foot end of the slot 76 in which it rides and thus link 73 pivots about pin '74 at its lower end to swing the screw about universal joint 69. Likewise upper link 72 is only pivotable about its outer end so that it pivots to exert an upward force on the end of foot portion 22 of the adjustable bed frame to raise same into the position shown in phantom in Figure 5. Rotation of shaft 67 and screw 68 in the opposite direction lowers foot portion 22 of the adjustable frame into normal position and continued rotation in this direction draws follower 71 away from the foot of the bed so that lower link 73 tends to move forward of the bed by the pin 74 sliding in slot 76. This forward movement of screw follower 71 transmits a forward force to the end of foot portion 22 of the adjustable bed frame through link 72 pivotally connected thereto. The pivotal connection of foot portion 22 upon extensions 25 of link rails 23 allows pivoting in only one direction by causing top surfaces of foot and extension members to contact, as shown, and further includes means to slide the pivoted ends of foot portion 22 slightly upward relative to link rails 23 by the provision of slanted slots in extensions 25 in which pins on foot portion 22 engage, as shown in Figure 5. Thus the longitudinal force exerted upon the end of foot portion 22 causes same to ride up on the pins in the pivotal engagement of foot portion 22 and extensions 25 of link rails 23 so that these members are slightly misaligned and this longitudinal force transmitted by link 72 from screw follower 71 thereby pivots the connection and raises the pivot so that link rails 23 and foot portion 22 are inclined with respect to each other, as shown in Figure 5. Raising or bending of the foot of the adjustable frame displaces the screw 68 vertically and universal joint 69 is thus required to accommodate this displacement while transmitting rotational motion to the worm gear.

It will be seen from the foregoing that the drive means has four drive positions wherein one of the discs is driven and by selection of these positions the head of the bed may be raised or lowered, the foot of the bed may be raised or lowered, and the foot of the bed may be bent upward to raise the knees of one in the bed.

What is claimed is:

1. Improved drive means for an adjustable bed having pivotal head and foot portions with adjustment means for each of said portions, comprising: two gear trains, each of said gear trains adapted to be connected to the adjacent adjustment means and each including a pair of parallel spaced discs with gears on the mutually presented surfaces thereof and a bevel gear engaging the gears on each disc, a drive shaft disposed intermediate said gear trains and being controllably displaceable toward each gear train, a pair of drive wheels mounted upon said drive shaft for rotation therewith and adapted for engagement with the discs of said gear trains to drive same, said drive wheels being displaceable longitudinally of said drive shaft for selective engagement with said gear train discs to drive said gear trains in opposite directions, and an electric motor connected to said drive shaft for rotating same.

2. Improved drive means for a hospital bed having a bed frame including pivotable head and foot portions and a pair of adjustment means connected one to the head portion and one to the foot portion for pivoting same, comprising: two sets of gears each having a bevel gear adapted to be connected to the adjacent adjustment means and a pair of parallel spaced discs having gears formed on the mutually presented surfaces thereof in engagement with the bevel gear whereby same is rotatable in opposite directions, a. drive shaft mounted for rotation intermediate said sets of gears perpendicular to the discs thereof, a pair of drive wheels adapted for driving engagement with individual discs of said sets of gears and mounted on said drive shaft for rotation therewith and having a separation thereon less than the spacing between discs of said sets of gears, said drive wheels being connected and being limitedly movable longitudinally of said drive shaft for alignment with different discs of each set of gears, a cradle carrying said drive shaft and being pivotable to engage an aligned driving wheel and a disc of one set of gears, an electric motor rotating said drive shaft, and motor control means actuated by pivoting of said cradle into engaging position of a drive wheel.

3. Improved drive means comprising: a cradle shaft, a pair of upstanding bars rigidly attached thereto, a drive shaft mounted for rotation on said bars and having a square center section, a pair of interconnected drive wheels mounted on the square drive shaft section for r0 tation therewith and being slidable longitudinally of said shaft, an electric motor, pulley means connecting said motor and drive shaft for rotating the latter, two sets of discs with the discs of each set having gear teeth formed on the mutually presented surfaces thereof and each set being aligned on opposite sides of said drive shaft with the discs thereof out of engagement with the drive wheels, a pair of bevel gears mounted with each gear engaging the geared surfaces on both discs of a set thereof, and a handle engaging said drive shaft for controllably aligning one of the drive wheels thereon with a pair of said discs and for displacing said drive shaft about said cradle shaft to engage the aligned drive wheel and one of said discs.

4. Adjusting means for an adjustable bed having a bed frame including a foot portion pivotally connected to a pair of pivotally mounted rails pivotally connected to the bed frame toward the head thereof and drive means including an electric motor, comprising: a shaft adapted to be connected to said drive means and arranged to extend longitudinally of said bed in rotatable relation to the frame thereof, an elongated screw extending to the foot of said bed frame from said shaft end, a universal joint joining said shaft and screw, an internally threaded cylinder engaging said screw for movement therealong with screw rotation, and link means engaging said cylinder and the end of said pivotable bed foot portion whereby the pivotal position of said foot portion is controllably adjustable, said link means including a first link pivotally connected to said cylinder and to the end of said foot portion and a second link pivotally connected to said cylinder and mounted to the bed frame for limited sliding engagement with the foot of said bed and longitudinally of said bed whereby rotation of said shaft in one direction raises the foot portion and shaft rotation in the opposite direction pivots said foot portion at said pivot point with the rails to raise the pivotal connection therebetween and disposes said foot portion and pivot rails at an angle to each other.

References Cited in the file of this patent UNITED STATES PATENTS 1,318,434 Buellesbach Oct. 14, 1919 1,422,405 Alguire July 11, 1922 1,790,435 Muller Jan. 27, 1931 1,908,530 Nixon May 9, 1933 2,084,396 Hennessy June 22, 1937 2,247,516 Murray July 1, 1941 2,349,701 Buttikofer May 23, 1944 2,630,720 Gambill Mar. 10, 1953 2,631,300 Murray Mar. 17, 1953 2,651,785 Berner Sept. 15, 1953 FOREIGN PATENTS 3,788 Great Britain 1886 16,455 Great Britain 1914 28,680 Denmark Oct. 24, 1921 

